Spring-Boot记录到Kafka:如何消除警告; 最佳做法

Question

我被问到如何从作为Oozie的Java动作运行的Spring Boot应用程序捕获日志输出.

我最初的想法是,可以编辑一些log4j属性来捕获YARN或Oozie中的应用程序日志.然后我发现,对于在各种群集节点上运行的特定应用程序,Kafka将是一种更容易捕获和聚合日志消息的方法.通过订阅主题而不是通过日志文件捕获来监视分布式系统要容易得多.

我注意到Kafka有一个log4j appender,所以我尝试创建一个最小的可重现的例子(发布在github上:https://github.com/alexwoolford/spring-boot-log-to-kafka-example).以下是一段摘录pom.xml:

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.4.4.RELEASE</version>
</parent>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter</artifactId>
        <exclusions>
            <exclusion>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-logging</artifactId>
            </exclusion>
            <exclusion>
                <groupId>org.springframework.boot</groupId>
                <artifactId>logback-classic</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-log4j</artifactId>
    </dependency>
    <dependency>
        <groupId>org.apache.kafka</groupId>
        <artifactId>kafka-log4j-appender</artifactId>
        <version>0.10.0.0</version>
    </dependency>
    <dependency>
        <groupId>net.logstash.log4j</groupId>
        <artifactId>jsonevent-layout</artifactId>
        <version>1.7</version>
    </dependency>
    <dependency>
        <groupId>commons-logging</groupId>
        <artifactId>commons-logging</artifactId>
        <version>1.2</version>
    </dependency>
</dependencies>

我的log4j.properties文件如下所示:

log4j.rootLogger=INFO
log4j.appender.KAFKA=org.apache.kafka.log4jappender.KafkaLog4jAppender
log4j.appender.KAFKA.layout=net.logstash.log4j.JSONEventLayoutV1
log4j.appender.KAFKA.topic=logs
log4j.appender.KAFKA.brokerList=hdp-single-node:6667
log4j.appender.KAFKA.syncSend=true
log4j.appender.KAFKA.producer.type=async
log4j.logger.io.woolford=INFO, KAFKA

这有效,除了它生成一个警告:

log4j:WARN No appenders could be found for logger (org.apache.kafka.clients.producer.ProducerConfig).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.

即使这个应用程序运行并执行我需要它,警告表明我错误配置了一些东西.你能看出需要改变什么吗？

另外,我注意到默认情况下Spring Boot使用Logback,我注意到有一个开源项目logback-kafka-appender,允许Logback追加到Kafka.Kafka log4j appender是Spring Boot登录Kafka的最佳方式吗？

Answer 1

对于Spring 2.4.4和reactive kafka，在application.properties中添加以下内容，减少了大量控制台消息

logging.level.org.apache.kafka=OFF

Answer 2

Log4j2有一个Kafka appender.有必要将spring-boot-starter-log4j2和jackson-databind工件添加到pom.xml:

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter</artifactId>
        <exclusions>
            <exclusion>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-logging</artifactId>
            </exclusion>
            <exclusion>
                <groupId>org.springframework.boot</groupId>
                <artifactId>logback-classic</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-log4j2</artifactId>
    </dependency>
    <dependency>
        <groupId>org.apache.kafka</groupId>
        <artifactId>kafka-log4j-appender</artifactId>
        <version>0.10.0.0</version>
        <exclusions>
            <exclusion>
                <groupId>org.slf4j</groupId>
                <artifactId>slf4j-log4j12</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>2.8.6</version>
    </dependency>
</dependencies>

然后我创建了一个XML格式的log4j2.xml文件:

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="info" name="spring-boot-log-to-kafka-example" packages="io.woolford">
    <Appenders>
        <Kafka name="kafkaAppender" topic="logs">
            <JSONLayout />
            <Property name="bootstrap.servers">hdp-single-node:6667</Property>
        </Kafka>
    </Appenders>
    <Loggers>
        <Root level="INFO">
            <AppenderRef ref="kafkaAppender"/>
        </Root>
        <Logger name="org.apache.kafka" level="WARN" />
    </Loggers>
</Configuration>

日志消息以JSON格式发送到Kafka,例如

{
    "timeMillis": 1485736022854,
    "thread": "Thread-1",
    "level": "INFO",
    "loggerName": "org.springframework.context.annotation.AnnotationConfigApplicationContext",
    "message": "Closing org.springframework.context.annotation.AnnotationConfigApplicationContext@20140db9: startup date [Sun Jan 29 17:26:52 MST 2017]; root of context hierarchy",
    "endOfBatch": false,
    "loggerFqcn": "org.apache.commons.logging.impl.SLF4JLocationAwareLog",
    "threadId": 19,
    "threadPriority": 5
}